No 10 said official guidance designed to suppress the spread of coronavirus did “not allow” for non-essential travel within the UK or overseas.
The pandemic has severely curtailed air travel although UK airlines are looking at how to operate after the lockdown.
Transport Secretary Grant Shapps said he would not book a summer break at the moment due to the current uncertainty.
Asked during an interview on Radio 4’s Today for his advice for people who would normally be considering their holiday plans, Mr Shapps said: “Clearly people will want to see what the trajectory of this disease is in the next few weeks.
“We are not seeing declines yet. I won’t be booking a summer holiday at this point, let’s put it that way.”
The body which represents travel companies reacted angrily, saying the comments were “thoughtless” and risked undermining confidence in the industry.
“It shows complete disregard for the UK travel industry, the hundreds of thousands of people it employs and the struggle it is facing in this current crisis,” Abta said in a statement.
“It would be better if the government focused on taking the necessary steps to support the sector.”
The lockdown – in which non-essential travel and public, non-family gatherings of more than two people are prohibited – has been extended for at least another three weeks, with people being urged to continue staying at home to save lives.
The outlook for the summer months remains highly uncertain, both for those who booked holidays before the pandemic struck and for those yet to make arrangements who hope to get away.
The Foreign Office has advised against all non-essential travel for an indefinite period.
Tui and Jet2 Holidays have cancelled all flights and package holidays until mid-May and mid-June respectively while the likes of BA, Virgin Atlantic and EasyJet have grounded many of their planes and furloughed staff in response to the travel restrictions introduced by countries around the world.
People have also been warned against domestic travel and visits to holiday and second homes, for fear they will spread the virus.
Home rental firm Airbnb has temporarily restricted UK bookings to key workers and “essential stays”.
A No 10 spokesman said travelling within the UK for holidays was “not something which the current guidelines allow for” and Foreign Office advice “continues to be that you should go abroad for essential travel only”.
“While we are making progress in our fight against coronavirus we are not able to say with certainty the point at which social distancing measures can be relaxed,” he added.
Aviation experts have warned that the crisis could fundamentally reshape the industry, with some airlines expected to suffer the same fate as FlyBe, which went into liquidation last month.
Carriers are looking at how to adapt their services in anticipation of social distancing rules remaining in place until a vaccine is found – thought to be a year to 18 months away.
EasyJet has said it plans to keep the middle seat on its planes empty when it resume flights.